Complications of distraction osteogenesis in short fourth metatarsals.

This study investigated 47 callus distractions performed in 31 patients who had only shortening of the fourth metatarsals (20 feet in 13 children and 27 feet in 18 adults). The average percentage of lengthening was 35% in children and 30% in adults. The average healing index was 69 days/cm in children and 75 days/cm in adults. In both groups, major complications were stiffness or subluxation of the metatarsophalangeal (MP) joint and minor complications were varus angulation at the distraction site and pin tract infection. The incidence of major complications was 30% (6/20) in children and 48% (13/27) in adults. The results in children were 14 excellent and 6 good; results in adults were 14 excellent, 8 good, 3 fair, and 2 poor, according to American Orthopaedic Foot and Ankle Society (AOFAS) score. The unfavorable results occurred in patients with combined short proximal phalanx who required extra lengthening and led to subluxation of the MP joint. Distraction lengthening is an effective treatment method for short fourth metatarsals, but subluxation or stiffness of the MP joint must be avoided for satisfactory results.